Sprint Car Fire Extinguisher - Open Wheel Flame Out

The most novel part of this article is the fact that a fire suppression system in Sprint Car is news. With the nature of open wheel racing being what it is-all out, minimum weight and maximum horsepower, the emphasis on extra safety equipment, especially fire suppression, is something you'll rarely see. With any race car, the danger of fire is always present. But with alcohol-burning Sprint Cars/Midgets, the dangers are that much more personal since the flames are far less visible and the safety crew can't tell the driver is on fire as easily.

The answer is a fire suppression system that is designed to work with the open wheel driver's needs and the confines of the Sprint Car/Midget chassis. Working with Riverview Racing Products in Riverview, Florida, a new Sprint Car fire suppression system was designed by Safecraft.

2/6The unit can be easily mounted to a chassis bar as shown here, note the silver tube. The system has two nozzles, both of which trigger automatically. One faces the fuel pump area (between the driver's legs) while the other nozzle points at the tail-tank.

With the space constraints in a Sprint Car, the new system had to be small, lightweight, and also function to protect the driver from a fire in the cockpit or around the tail-tank. For this reason, the system had to have two nozzles that would trigger automatically. One nozzle points toward the fuel pump area (between the driver's legs), while the other points at the tail-tank.

The body of the system is a 16 inch laser-welded stainless steel cylinder containing a pound of Halon 1211. On one end of the cylinder are the attachment points for the forward and rear nozzle lines, and on the other end are the fill port and the pressure gauge.

The system needs no input from the driver, which is critical if he or she gets knocked out in a wreck. The nozzles will trigger automatically in the event of a fire. They also use heat sensitive actuators that are triggered at different temperature settings. The front nozzle by the driver's legs and fuel pump has the trigger set to 200 degrees F. The rear nozzle is set to trigger at 286 degrees F. The reason for the increased temperature of the rear trigger is that the rear nozzle has the potential to be mounted near the brake rotor, so the decision was made to increase the temperature to make sure the nozzle wouldn't go off from ambient brake heat alone.

Another major decision in the design was to balance the weight of the system with the coverage that the chemical would provide. When a nozzle is triggered, the entire pound of Halon 1211 will be exhausted. The Halon will provide a coverage area of 50 cubic feet. For the Sprint Car cockpit and extinguishing a tail-tank fire, the 50 cubic feet of coverage will be more than enough. Even if the chemical was changed to the DuPont FE-36, which provides less volume, there will still be enough coverage to suppress most fires.

3/6Note the nozzle for the extinguisher protruding from under the seat. Pointed toward the fuel pump this mounting location also ensures that the extinguishing media can fill the cockpit and keep fire away from the driver's body.

The tight confines of the Sprint Car chassis provides another unique aspect of this system in how it's mounted on the chassis. The cylinder is to be mounted vertically, on the back of the seat or on an upright chassis bar. When the unit is mounted in the car, the lines come off the bottom of the cylinder while the gauge and fill valve are facing up. The lines are run so that they are out of the way of any moving objects and away from the driver's legs. It's important to use insulating clamps when mounting the lines and the cylinder. Any lines and fittings that are subject to excessive vibration are also subject to breaking. This is, by the way, true of mounting any fire suppression system, not just this one.

The unit is available from Riverview Racing Products in Tampa, Florida, at a cost of approximately $325. Hopefully, you'd never need to use it, but in a case where the unit was triggered, it can be rebuilt by sending it out for service. Riverview performs this service which includes replacing the triggered nozzle, pressure testing the unit, and refilling it with the extinguishing chemical. The cost of the rebuild would be approximately $75 to $100.

Some of the most dangerous fires I've seen in circle-track racing, have been in Sprint Car, Modified, and Midget chassis. The firewalls are smaller, the fuel cells/tail-tanks are more exposed, and the drivers have less body work around them. Having a fire suppression system is so important considering the time it takes from the start of the fire to the arrival on scene of even the best safety crew. Now that a system has been designed with the open wheel racer in mind, it's even an easier choice to install one.